1 /* 2 * libunbound/context.c - validating context for unbound internal use 3 * 4 * Copyright (c) 2007, NLnet Labs. All rights reserved. 5 * 6 * This software is open source. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * Redistributions of source code must retain the above copyright notice, 13 * this list of conditions and the following disclaimer. 14 * 15 * Redistributions in binary form must reproduce the above copyright notice, 16 * this list of conditions and the following disclaimer in the documentation 17 * and/or other materials provided with the distribution. 18 * 19 * Neither the name of the NLNET LABS nor the names of its contributors may 20 * be used to endorse or promote products derived from this software without 21 * specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 24 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 25 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 26 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 27 * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 28 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED 29 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 30 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 31 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 32 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 33 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 34 */ 35 36 /** 37 * \file 38 * 39 * This file contains the validator context structure. 40 */ 41 #include "config.h" 42 #include "libunbound/context.h" 43 #include "util/module.h" 44 #include "util/config_file.h" 45 #include "util/net_help.h" 46 #include "services/modstack.h" 47 #include "services/localzone.h" 48 #include "services/cache/rrset.h" 49 #include "services/cache/infra.h" 50 #include "services/authzone.h" 51 #include "util/data/msgreply.h" 52 #include "util/storage/slabhash.h" 53 #include "sldns/sbuffer.h" 54 55 int 56 context_finalize(struct ub_ctx* ctx) 57 { 58 struct config_file* cfg = ctx->env->cfg; 59 verbosity = cfg->verbosity; 60 if(ctx->logfile_override) 61 log_file(ctx->log_out); 62 else log_init(cfg->logfile, cfg->use_syslog, NULL); 63 config_apply(cfg); 64 if(!modstack_setup(&ctx->mods, cfg->module_conf, ctx->env)) 65 return UB_INITFAIL; 66 log_edns_known_options(VERB_ALGO, ctx->env); 67 ctx->local_zones = local_zones_create(); 68 if(!ctx->local_zones) 69 return UB_NOMEM; 70 if(!local_zones_apply_cfg(ctx->local_zones, cfg)) 71 return UB_INITFAIL; 72 if(!auth_zones_apply_cfg(ctx->env->auth_zones, cfg, 1)) 73 return UB_INITFAIL; 74 if(!ctx->env->msg_cache || 75 cfg->msg_cache_size != slabhash_get_size(ctx->env->msg_cache) || 76 cfg->msg_cache_slabs != ctx->env->msg_cache->size) { 77 slabhash_delete(ctx->env->msg_cache); 78 ctx->env->msg_cache = slabhash_create(cfg->msg_cache_slabs, 79 HASH_DEFAULT_STARTARRAY, cfg->msg_cache_size, 80 msgreply_sizefunc, query_info_compare, 81 query_entry_delete, reply_info_delete, NULL); 82 if(!ctx->env->msg_cache) 83 return UB_NOMEM; 84 } 85 ctx->env->rrset_cache = rrset_cache_adjust(ctx->env->rrset_cache, 86 ctx->env->cfg, ctx->env->alloc); 87 if(!ctx->env->rrset_cache) 88 return UB_NOMEM; 89 ctx->env->infra_cache = infra_adjust(ctx->env->infra_cache, cfg); 90 if(!ctx->env->infra_cache) 91 return UB_NOMEM; 92 ctx->finalized = 1; 93 return UB_NOERROR; 94 } 95 96 int context_query_cmp(const void* a, const void* b) 97 { 98 if( *(int*)a < *(int*)b ) 99 return -1; 100 if( *(int*)a > *(int*)b ) 101 return 1; 102 return 0; 103 } 104 105 void 106 context_query_delete(struct ctx_query* q) 107 { 108 if(!q) return; 109 ub_resolve_free(q->res); 110 free(q->msg); 111 free(q); 112 } 113 114 /** How many times to try to find an unused query-id-number for async */ 115 #define NUM_ID_TRIES 100000 116 /** find next useful id number of 0 on error */ 117 static int 118 find_id(struct ub_ctx* ctx, int* id) 119 { 120 size_t tries = 0; 121 ctx->next_querynum++; 122 while(rbtree_search(&ctx->queries, &ctx->next_querynum)) { 123 ctx->next_querynum++; /* numerical wraparound is fine */ 124 if(tries++ > NUM_ID_TRIES) 125 return 0; 126 } 127 *id = ctx->next_querynum; 128 return 1; 129 } 130 131 struct ctx_query* 132 context_new(struct ub_ctx* ctx, const char* name, int rrtype, int rrclass, 133 ub_callback_type cb, ub_event_callback_type cb_event, void* cbarg) 134 { 135 struct ctx_query* q = (struct ctx_query*)calloc(1, sizeof(*q)); 136 if(!q) return NULL; 137 lock_basic_lock(&ctx->cfglock); 138 if(!find_id(ctx, &q->querynum)) { 139 lock_basic_unlock(&ctx->cfglock); 140 free(q); 141 return NULL; 142 } 143 lock_basic_unlock(&ctx->cfglock); 144 q->node.key = &q->querynum; 145 q->async = (cb != NULL || cb_event != NULL); 146 q->cb = cb; 147 q->cb_event = cb_event; 148 q->cb_arg = cbarg; 149 q->res = (struct ub_result*)calloc(1, sizeof(*q->res)); 150 if(!q->res) { 151 free(q); 152 return NULL; 153 } 154 q->res->qname = strdup(name); 155 if(!q->res->qname) { 156 free(q->res); 157 free(q); 158 return NULL; 159 } 160 q->res->qtype = rrtype; 161 q->res->qclass = rrclass; 162 163 /* add to query list */ 164 lock_basic_lock(&ctx->cfglock); 165 if(q->async) 166 ctx->num_async ++; 167 (void)rbtree_insert(&ctx->queries, &q->node); 168 lock_basic_unlock(&ctx->cfglock); 169 return q; 170 } 171 172 struct alloc_cache* 173 context_obtain_alloc(struct ub_ctx* ctx, int locking) 174 { 175 struct alloc_cache* a; 176 int tnum = 0; 177 if(locking) { 178 lock_basic_lock(&ctx->cfglock); 179 } 180 a = ctx->alloc_list; 181 if(a) 182 ctx->alloc_list = a->super; /* snip off list */ 183 else tnum = ctx->thr_next_num++; 184 if(locking) { 185 lock_basic_unlock(&ctx->cfglock); 186 } 187 if(a) { 188 a->super = &ctx->superalloc; 189 return a; 190 } 191 a = (struct alloc_cache*)calloc(1, sizeof(*a)); 192 if(!a) 193 return NULL; 194 alloc_init(a, &ctx->superalloc, tnum); 195 return a; 196 } 197 198 void 199 context_release_alloc(struct ub_ctx* ctx, struct alloc_cache* alloc, 200 int locking) 201 { 202 if(!ctx || !alloc) 203 return; 204 if(locking) { 205 lock_basic_lock(&ctx->cfglock); 206 } 207 alloc->super = ctx->alloc_list; 208 ctx->alloc_list = alloc; 209 if(locking) { 210 lock_basic_unlock(&ctx->cfglock); 211 } 212 } 213 214 uint8_t* 215 context_serialize_new_query(struct ctx_query* q, uint32_t* len) 216 { 217 /* format for new query is 218 * o uint32 cmd 219 * o uint32 id 220 * o uint32 type 221 * o uint32 class 222 * o rest queryname (string) 223 */ 224 uint8_t* p; 225 size_t slen = strlen(q->res->qname) + 1/*end of string*/; 226 *len = sizeof(uint32_t)*4 + slen; 227 p = (uint8_t*)malloc(*len); 228 if(!p) return NULL; 229 sldns_write_uint32(p, UB_LIBCMD_NEWQUERY); 230 sldns_write_uint32(p+sizeof(uint32_t), (uint32_t)q->querynum); 231 sldns_write_uint32(p+2*sizeof(uint32_t), (uint32_t)q->res->qtype); 232 sldns_write_uint32(p+3*sizeof(uint32_t), (uint32_t)q->res->qclass); 233 memmove(p+4*sizeof(uint32_t), q->res->qname, slen); 234 return p; 235 } 236 237 struct ctx_query* 238 context_deserialize_new_query(struct ub_ctx* ctx, uint8_t* p, uint32_t len) 239 { 240 struct ctx_query* q = (struct ctx_query*)calloc(1, sizeof(*q)); 241 if(!q) return NULL; 242 if(len < 4*sizeof(uint32_t)+1) { 243 free(q); 244 return NULL; 245 } 246 log_assert( sldns_read_uint32(p) == UB_LIBCMD_NEWQUERY); 247 q->querynum = (int)sldns_read_uint32(p+sizeof(uint32_t)); 248 q->node.key = &q->querynum; 249 q->async = 1; 250 q->res = (struct ub_result*)calloc(1, sizeof(*q->res)); 251 if(!q->res) { 252 free(q); 253 return NULL; 254 } 255 q->res->qtype = (int)sldns_read_uint32(p+2*sizeof(uint32_t)); 256 q->res->qclass = (int)sldns_read_uint32(p+3*sizeof(uint32_t)); 257 q->res->qname = strdup((char*)(p+4*sizeof(uint32_t))); 258 if(!q->res->qname) { 259 free(q->res); 260 free(q); 261 return NULL; 262 } 263 264 /** add to query list */ 265 ctx->num_async++; 266 (void)rbtree_insert(&ctx->queries, &q->node); 267 return q; 268 } 269 270 struct ctx_query* 271 context_lookup_new_query(struct ub_ctx* ctx, uint8_t* p, uint32_t len) 272 { 273 struct ctx_query* q; 274 int querynum; 275 if(len < 4*sizeof(uint32_t)+1) { 276 return NULL; 277 } 278 log_assert( sldns_read_uint32(p) == UB_LIBCMD_NEWQUERY); 279 querynum = (int)sldns_read_uint32(p+sizeof(uint32_t)); 280 q = (struct ctx_query*)rbtree_search(&ctx->queries, &querynum); 281 if(!q) { 282 return NULL; 283 } 284 log_assert(q->async); 285 return q; 286 } 287 288 uint8_t* 289 context_serialize_answer(struct ctx_query* q, int err, sldns_buffer* pkt, 290 uint32_t* len) 291 { 292 /* answer format 293 * o uint32 cmd 294 * o uint32 id 295 * o uint32 error_code 296 * o uint32 msg_security 297 * o uint32 length of why_bogus string (+1 for eos); 0 absent. 298 * o why_bogus_string 299 * o the remainder is the answer msg from resolver lookup. 300 * remainder can be length 0. 301 */ 302 size_t pkt_len = pkt?sldns_buffer_remaining(pkt):0; 303 size_t wlen = (pkt&&q->res->why_bogus)?strlen(q->res->why_bogus)+1:0; 304 uint8_t* p; 305 *len = sizeof(uint32_t)*5 + pkt_len + wlen; 306 p = (uint8_t*)malloc(*len); 307 if(!p) return NULL; 308 sldns_write_uint32(p, UB_LIBCMD_ANSWER); 309 sldns_write_uint32(p+sizeof(uint32_t), (uint32_t)q->querynum); 310 sldns_write_uint32(p+2*sizeof(uint32_t), (uint32_t)err); 311 sldns_write_uint32(p+3*sizeof(uint32_t), (uint32_t)q->msg_security); 312 sldns_write_uint32(p+4*sizeof(uint32_t), (uint32_t)wlen); 313 if(wlen > 0) 314 memmove(p+5*sizeof(uint32_t), q->res->why_bogus, wlen); 315 if(pkt_len > 0) 316 memmove(p+5*sizeof(uint32_t)+wlen, 317 sldns_buffer_begin(pkt), pkt_len); 318 return p; 319 } 320 321 struct ctx_query* 322 context_deserialize_answer(struct ub_ctx* ctx, 323 uint8_t* p, uint32_t len, int* err) 324 { 325 struct ctx_query* q = NULL ; 326 int id; 327 size_t wlen; 328 if(len < 5*sizeof(uint32_t)) return NULL; 329 log_assert( sldns_read_uint32(p) == UB_LIBCMD_ANSWER); 330 id = (int)sldns_read_uint32(p+sizeof(uint32_t)); 331 q = (struct ctx_query*)rbtree_search(&ctx->queries, &id); 332 if(!q) return NULL; 333 *err = (int)sldns_read_uint32(p+2*sizeof(uint32_t)); 334 q->msg_security = sldns_read_uint32(p+3*sizeof(uint32_t)); 335 wlen = (size_t)sldns_read_uint32(p+4*sizeof(uint32_t)); 336 if(len > 5*sizeof(uint32_t) && wlen > 0) { 337 if(len >= 5*sizeof(uint32_t)+wlen) 338 q->res->why_bogus = (char*)memdup( 339 p+5*sizeof(uint32_t), wlen); 340 if(!q->res->why_bogus) { 341 /* pass malloc failure to the user callback */ 342 q->msg_len = 0; 343 *err = UB_NOMEM; 344 return q; 345 } 346 q->res->why_bogus[wlen-1] = 0; /* zero terminated for sure */ 347 } 348 if(len > 5*sizeof(uint32_t)+wlen) { 349 q->msg_len = len - 5*sizeof(uint32_t) - wlen; 350 q->msg = (uint8_t*)memdup(p+5*sizeof(uint32_t)+wlen, 351 q->msg_len); 352 if(!q->msg) { 353 /* pass malloc failure to the user callback */ 354 q->msg_len = 0; 355 *err = UB_NOMEM; 356 return q; 357 } 358 } 359 return q; 360 } 361 362 uint8_t* 363 context_serialize_cancel(struct ctx_query* q, uint32_t* len) 364 { 365 /* format of cancel: 366 * o uint32 cmd 367 * o uint32 async-id */ 368 uint8_t* p = (uint8_t*)reallocarray(NULL, sizeof(uint32_t), 2); 369 if(!p) return NULL; 370 *len = 2*sizeof(uint32_t); 371 sldns_write_uint32(p, UB_LIBCMD_CANCEL); 372 sldns_write_uint32(p+sizeof(uint32_t), (uint32_t)q->querynum); 373 return p; 374 } 375 376 struct ctx_query* context_deserialize_cancel(struct ub_ctx* ctx, 377 uint8_t* p, uint32_t len) 378 { 379 struct ctx_query* q; 380 int id; 381 if(len != 2*sizeof(uint32_t)) return NULL; 382 log_assert( sldns_read_uint32(p) == UB_LIBCMD_CANCEL); 383 id = (int)sldns_read_uint32(p+sizeof(uint32_t)); 384 q = (struct ctx_query*)rbtree_search(&ctx->queries, &id); 385 return q; 386 } 387 388 uint8_t* 389 context_serialize_quit(uint32_t* len) 390 { 391 uint8_t* p = (uint8_t*)malloc(sizeof(uint32_t)); 392 if(!p) 393 return NULL; 394 *len = sizeof(uint32_t); 395 sldns_write_uint32(p, UB_LIBCMD_QUIT); 396 return p; 397 } 398 399 enum ub_ctx_cmd context_serial_getcmd(uint8_t* p, uint32_t len) 400 { 401 uint32_t v; 402 if((size_t)len < sizeof(v)) 403 return UB_LIBCMD_QUIT; 404 v = sldns_read_uint32(p); 405 return v; 406 } 407